1. Field of the Invention
The invention relates to an image forming apparatus configured to pick up recording sheets from a sheet tray and form images onto the respective recording sheets by a recording unit.
2. Description of the Related Art
Known image forming apparatuses pick up recording sheets, e.g., Standard-size sheets, A4-size sheets, and the like from a sheet tray and to form images onto the respective recording sheets. A known image forming apparatus, for example, an inkjet printer, may form images onto a plurality of recording sheets. The image forming apparatus is configured to pick up a recording sheet in a stack of recording sheets from a sheet tray, convey the recording sheet to a predetermined recording position, and form an image onto the recording sheet at the recording position. The image forming apparatus is configured to form images onto respective recording sheets by repeatedly performing a series of the above processes for the printing operation.
A known image forming apparatus may include a sheet conveying mechanism that includes a sheet feed roller and a pair of conveyor rollers. The sheet feed roller may be in contact with a recording sheet accommodated in the sheet tray. The pair of conveyor rollers are disposed downstream from the sheet feed roller and upstream from the recording position in the sheet conveying path. The sheet conveying mechanism further includes a pair of discharge rollers disposed downstream from the recording position in the sheet conveying path. The sheet conveying mechanism is configured to convey a recording sheet by the sheet feed roller, the conveyor rollers, and the discharge rollers.
In the known image forming apparatus, a recording sheet placed on the sheet tray is conveyed toward an upstream part of the sheet conveying path by the rotation of the sheet feed roller. The recording sheet fed from the sheet tray is pinched between the conveyor rollers and is further conveyed to the recording position by the rotation of the conveyor rollers. The recording sheet, on which an image was formed, is then pinched between the discharge rollers and is discharged from the image forming apparatus by the rotation of the discharge rollers.
As a method of performing a continuous printing operation, a known inkjet printer will, at the completion of discharge of the recording sheet after an image forming operation is performed on the recording sheet, a subsequent recording sheet is fed from a sheet tray. Nevertheless, in the known continuous printing operation, the image forming operation may not be performed onto the next recording sheet until the preceding recording sheet is completely discharged after the image forming operation, which may decrease throughput, e.g., the number of sheets that can be printed within a predetermined time period
A known image forming apparatus also may not correct skew of recording sheets for second and subsequent pages. Thus, the recording sheets for the second and subsequent pages may reach the recording position with a skewed orientation. As a result, an image may be formed at an undesirable position on the recording sheet or paper jam may occur in the known image forming apparatus.